CONFIG_AS_HAS_ARMV8_3 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm64
default or selected kernelversion does not have config value CONFIG_AS_HAS_ARMV8_3.
Result is shown for kernelversion 6.9.9

CONFIG_AS_HAS_ARMV8_3 (not configurable)

configname: CONFIG_AS_HAS_ARMV8_3

Linux Kernel Configuration
└─>Kernel Features
└─>ARMv8.3 architectural features
└─>AS_HAS_ARMV8_3
In linux kernel since version 6.3 (release Date: 2023-04-23)